I found a reply in an old thread detailing what they saw on stream of someone who took SN, I think it's the most detailed account I've seen so far.
23:55 mixing SN (25g/50ml weight: 90kg; 2 glasses) Position is a comfy chair
23:57 drank first glass in a second; taste was salty but remained calm
23:58 lit up a cigarette
23:59 feels it in throat, still able to walk (went to the sink to rinse and came back)
00:00 threw up, seems a bit in distress, threw up multiple times
Prince offers to sing, he's able to respond, Prince sings a nice lullaby
00:01 seems to be in distress, constant vomiting
00:02 says "sick", went to grab a cloth, returned abruptly with cloth, vomiting again
00:03 "my hands are tingling"
00:04 almost vomited but was able to hold it back, "my heart is beating fast"
Can communicate but obviously seems sick
00:05 "it's tingling now" "uncomfortable but doesn't hurt"
00:06 "I'm very restless"
00:07 starts shaking a bit, not able to communicate but can move his hands and head
00:08 convulsing (a bit violently for a few seconds), saliva/vomit shot out of his mouth, headphone fell off but was able to put it back to his ears - his last confirmed voluntary movement
00:09 light shaking, tries to move head
00:10 makes strange sounds but not able to speak
00:11 a few heavy convulsions but still in position, headphone on, saliva shot out again
00:11 makes sounds again, seems like he tries to speak but can't
00:12 not much movement, occasionally straightens up then falls back to chair
00:13 sounds continue
00:14 possibly unconscious (it could have happened sooner than this time)
00:15 visibly more blue now and pale
00:16 snorts continuously, might be the so called "death rattle"
00:17-20 situation is the same as above
00:19 one straightening up, and one louder sound, like a grasp for air
00:21 sounds are becoming less frequent, there are some random involuntary movements but not much (mostly mouth opening)
00:22 almost ceased movements
00:24 little sound and movement
00:25 getting near; still in the chair, mouth and eyes are open, he's obviously not there
00:26 no more sounds, sometimes moves a little bit
00:28 no more movements
conclusion: hard to watch someone die but seems relatively peaceful, just as expected; threw up a lot at the beginning, at the time of the convulsions he did not seem to realize what was happening, he did not drink the second glass
Original thread:
https://sanctioned-suicide.net/threads/goodbye-thread.53182/